Consumer Reports is about as bias-free as your going to get. Sure they might not be perfect, but they are not hired by Apple or competitors and they don't have advertising accounts. Personally I'll be very interested in what their testing reveals either pro or con.
But what relevance do they have today? How many people look to consumer reports before they buy a product? My guess is not many. But no doubt what ever test they do will be all over the media, especially if it's bad for Apple.